With the rapid development of display technology, touch screen panels have been gradually spreading throughout people's life. Nowadays, touch screen panels, according to configurations, can be classified into: add-on mode touch panels, on-cell touch panels, and in-cell touch panels. An add-on mode touch panel is a liquid crystal display having a touch function and is formed by producing a touch screen panel and a liquid crystal display (LCD) separately and then attaching them together. An add-on mode touch panel has disadvantages such as higher manufacturing costs, lower light transmittance, thicker module, and so on. An in-cell touch panel has touch control electrodes for a touch screen panel embedded inside a liquid crystal display, can decrease the whole thickness of the module, can have significantly reduced manufacturing costs for the touch screen panel, and thus become attractive to main manufacturers.
At present, a capacitive in-cell touch panel is realized by directly adding touch control scanning lines and touch control sensing lines on a current TFT (thin film transistor) array substrate, that is, on a surface of the TFT array substrate, manufacturing two layers of stripe-like electrodes that are non-coplanar but intersect with each other. These two layers of electrodes respectively serve as touch control driving lines and touch control sensing lines of the touch screen panel, and at a non-coplanar intersection between two of the electrodes, there forms a mutual capacitor. The working process of the capacitive in-cell touch panel is that: when the electrodes serving as touch control driving lines are loaded with touch control driving signals, the voltage signals coupled out by the touch control sensing lines via the mutual capacitor are detected, and during this process, when a human body contacts the touch screen panel, the electric field of the human body will act on the mutual capacitor, making the capacitance value of the mutual capacitor change and then changing the voltage signals coupled out by the touch control sensing lines, and the contact positions can be determined according to changes of the voltage signals.
In the configuration design of the abovementioned capacitive in-cell touch panel, the touch control signals, loaded over the touch control scanning lines and the touch control sensing lines that are added on the current TFT array substrate, will mutually interfere with the original display signals in the TFT array substrate, which not only has an influence on the quality of liquid crystal display pictures but also deteriorates the reliability of touch control operations.